Abstract : This chapter discusses the ongoing transformations of the French defence support. Considering the importance of economic activities related to defence support, this contribution aims at discussing the evolution of defence support and its costs for the State. The literature in defence economics presents very little analysis of defence support in its different forms. Neither space nor base locations have been deeply analysed in such a literature. We try to bridge this gap in an original research framework. We focus on the Maintenance, Repair and Overhaul (MRO) of defence platforms. More particularly, we focus on the array of measures that surround French defence support in MRO since the end of the 1990s. Considering both economic and spatial leverages, how can the organisation of MRO be optimised? With concepts from spatial economics, we propose a new look on the defence support system. We examine new economic interconnections (e.g. Public Private Partnerships and outsourcing) between military and civilian activities. More broadly speaking, this path of research could help us to better understand the new type of economic interrelations between defence organisation and 'territory' as a social fabric.